A mysterious environmental group fronted by dubious online identities — including one endorsed by a former Liberal party staffer — has spent more than a year trying to forge ties with the Adani protest movement while urging activists to target Clive Palmer.

Key points:

An 'environmental organisation' Gatekeepers of Our Reef has spent more than a year cultivating contacts in the Stop Adani protest movement but is targeting Clive Palmer

It is fronted by dubious online identities, one of them endorsed by a then-staffer for a WA Liberal senator

A volunteer says he has been duped and activists accuse the group of infiltrating the Stop Adani movement to try to gain inside information on protest tactics

The Gatekeepers of Our Reef group is run by people who carefully hid their tracks while approaching Stop Adani organisers, who say they sought information on protest tactics while mounting a strange campaign against Mr Palmer.

Roger Mann, who volunteered to run the Gatekeepers group's social media from regional Victoria, said he was duped by people who cultivated him for months online.

Last July, another group organiser, calling himself "Ben Ferguson", posted on international jobsites in Sydney, Brisbane and the Gold Coast offering $19 an hour for "tech-savvy students" to promote "an environmental organisation" on university campuses.

He promised "a large bonus at the end of the project for a job well done, defined in advance with KPI's".

An international student who responded to the Brisbane advertisement in turn received no response.

Ben Pennings, a Stop Adani movement organiser and former Greens candidate, has maintained contact with the Gatekeepers since last year, said the group immediately aroused the suspicions of experienced activists familiar with attempts by private investigators to infiltrate green protest groups.

"Gatekeepers of Our Reef contacted me on Twitter … they were curious about direct action and piqued my interest," he said.

"We ask around and try to get people to vouch whether people online are real … particularly Western Australia where Gatekeepers say they're from, and no-one knew hide nor hair of them."

Both Mr Mann and Mr Pennings said they had spoken by phone to Gatekeepers organisers, who always called them from unlisted numbers.

The only other contact details were email addresses and social media profiles.

The ABC sent queries to those email addresses but received no response.

Posts on the Gatekeepers Facebook page briefly disappeared after the ABC's enquiries.

'Good at keeping themselves secret'

Mr Pennings said Mr Ferguson told him the group was eager for the Stop Adani movement to promote a video it had produced about Clive Palmer during this election campaign, because his "biggest concern" was the prospect of Mr Palmer holding the balance of power in the Senate.

"There is obviously some money behind it — their video was quite professional," he said.

"They were offering jobs to international students to promote the organisation. They're good at keeping themselves secret.